Smaragdmos, Homalothecium lutescens, vormde rijkelijk sporenkapsels in de zachte, regenrijke winter van 1994/95

During the last decades capsules of Homalothecium lutescens have not been recorded from The Netherlands. Recently a number of capsule bearing populations have been met with in different parts of the coastal districts (sand dunes). Several possible causal factors for this remarkable phenomenon are taken into consideration. Of these, the substantial change in the weather conditions since 1988, seems the most exceptable explanation. In the last 7 years the average winter temperatures have been 1° C higher than in the 60 years before. The average yearly rain fall in this period increased with more than 10 percent. Moreover the water temperature of the North Sea increased considerably, a condition which has a positive influence on the formation of early morning dew in the coastal sand dunes. The microhabitats in which the capsules have been found, were extraordinary sheltered against drying out by their position on fairly steep north slopes or by their situation on the verge of a forest.